Cummins/Onan — Alternator and Engine Removal

Repair & overhaul

From a Cummins/Onan service manual covering: C13 N6H, C13N6H, C17 N6H, C17N6H, C20 N6, C20N6H, RS13A. Check it applies to your exact model before use.

Applies to: Cummins/Onan C13 N6H, Cummins/Onan C17 N6H, Cummins/Onan C20 N6, Cummins/Onan RS13A

Procedure

1. Obtain the tools and parts required. Disconnect the AC utility source. Open the hood.
2. Remove the intake air and exhaust panels.
3. Remove the negative battery cable first, then the positive battery cable. Remove the battery.
4. Disconnect the HMI (P1 on the display) and AC battery charger (BC-P).
5. Remove the control access and exhaust access panels.
6. Remove the alternator-end panel, hood, and cross braces, leaving the engine-end panel in place.
7. Remove the alternator fan: block it with a 2x4, loosen the rotor retaining nut, double nut the through-stud, and use a gear puller.
8. Remove the exhaust muffler and the exhaust-end inner panel.
9. Disconnect the alternator leads from the circuit breaker, noting the CT orientation.
10. Remove the oil filter access panel, oil cooler mounting bolts, and inner panels.
11. Remove the stator: remove the brush block, disconnect heater leads, support the stator, remove mount nuts and through-stud nuts, remove the end bell, o-ring and bearing.
12. Remove the rotor using the rotor removal tool and an M14 x 2.0 bolt.
13. Remove the engine: drain oil, remove linkages, fuel line, airbox, mixer and intake manifold, wiring, exhaust manifold, isolators, and engine.

Full service-parts list: Cummins/Onan C20 N6 →

Source: Cummins/Onan service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.

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